EDEN PRAIRIE, Minn. -- On Friday, Chris Cook expressed hope he'd get one more shot to right his rookie season.

He didn't get the chance.

The Minnesota Vikings on Tuesday placed their top draft pick on injured reserve -- a sad but fitting end to a campaign marked by an encouraging training camp, two knee surgeries and two benchings as he tried to play through persistent pain and swelling before the Vikings shut him down on Nov. 26.

"We just felt like for him and for our future it's better to not continue to try to get him back out here," interim coach Leslie Frazier said of Cook, who started five games at cornerback and appeared in another, finishing with 24 tackles (20 solo) and three pass break-ups.

"He needed to rest those knees after two surgeries this season. So, we're going to place him on IR and give him a chance to rest and get ready for the 2011 season."

The Vikings replaced Cook on the 53-man roster by promoting tackle Thomas Welch from the practice squad. Welch (6-foot-6, 300 pounds) joined the Vikings' practice squad on Sept. 6 -- two days after being waived the New England Patriots, who drafted him in the seventh round out of Vanderbilt.

It's the third time in four weeks the Vikings have placed a player on IR because of a knee injury. Right guard Anthony Herrera blew out an anterior cruciate ligament on Nov. 24 against Green Bay and running back Albert Young injured a medial collateral ligament on Dec. 5 against Buffalo.

Peterson's OK

Halfback Adrian Peterson had a "slight" bruise on his right knee after Monday's collision with quarterback Tarvaris Jackson, Frazier said, "but he's going to be fine."

Peterson was trying to evade a slot blitzer when his knee hit Jackson's right knee in the second quarter of the Vikings' loss to the New York Giants, leaving both players writhing on the ground.

Both returned on the next series, but Peterson never got going. His 14 rushes produced only 26 yards and a 1.9 per-carry average -- the worst he's fared in either category since he ran 13 times for 19 yards (1.5 average) last Dec. 6 at Arizona.

"I don't know if that necessarily had a great deal of effect on his play," Frazier said of the knee. "He ran just as hard as he's ever run -- there just wasn't much running room for him."

Health watch

In other injury-related updates:

• Left end Ray Edwards (high ankle sprain) is "on the mend" after missing two straight games, Frazier said. "We're hoping to have him back. We'll find out a little bit more when Thursday rolls around."

• "All indications" are that receiver Percy Harvin (migraines) will practice on Thursday, Frazier said. "Now it's just a matter of getting through the week to have him ready for Monday night."

• Left guard Steve Hutchinson (broken thumb) remains "probably day to day," Frazier said, "just to see how he can tolerate the pain he has and the swelling he has as well. We'll see as time goes on."

Quick hits

• Frazier reiterated he doesn't anticipate a letdown now that the Vikings are mathematically eliminated from playoff contention. "One of the keys to us is, although we're not a playoff team in 2010, we still have a lot to play for," Frazier said. "We still have a lot of guys with a lot of pride on our team who want to be successful, and that's how we'll approach it going forward."

• Frazier wouldn't say whether he disagreed with the illegal block against MLB Jasper Brinkley that wiped out HB Lorenzo Booker's 96-yard kick-return touchdown on Monday. But Frazier did strongly hint the call was questionable. "I know Jasper gave great effort, and when you see it, you just wish we had scored on that play," Frazier said. "Wish it had held up. There were a lot of good things on that play. Lot of good things, and just wish it had held up."